Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02498520 2000-08-09
center Be~azn Car with Increased Load Capacity
This application is a divisional of Canadian Patent Application
No. 2,315,535 filed August 9, 2000.
Ba~~kground of the Invention
The invention relates generally to railcars, and more
particularly, to a center beam car.
Center beam cars have proven to be useful zn
transportation of various materials, including bulk
materials such as l.t~mber prod.ucte which are of high volume
azzd low density. However, there remains room for improvement
in certain areas.
First, the usax7le volume capacity of the center beam
car is often reached before the caz~s weight capacity is
reached. This results in inefficiency, in that the weight
caxrying capacity of the car is not fully utilized. One of
the objects of the ~.nvention is to provide a center beam car
is having capacity to carry loads of increased volume.
Another area for improvement relates to efficiency in
loading and unloading the cars. While center beam cars can
be loaded and unloaded efficiently with forklifts, loading
and unloading by overhead crane is difficult due to the fact
that the top chord typically overhangs the lvad_ It is a
general object of the invention to provide a center beam car
which can be more easily loaded by overhead crane.
A further area for improvement concerns securing loads
in place. After a car has been loaded, to secure the load
in place, workers have generally been required to climb onto
the load to secure c;~.bles to the center beam. Winches have
been provided on each side of the car, fixed to the side
sills at predetermined intervals. Cables are pulled from
the winches to the center beam to secure the load. Later,
when the car is to b~~ unloaded, workers must again climb
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onto the car and release the cable ends from the center
beams. The need for workers tv climb onto the car after
loading and prior t.o unloadi.ng adds time and expense to the
loading and unloading operations. Application of the cables
is further complicated by the fact that it has generally
been necessary to employ corner protectors at the upper
corners of the lading to protect the lading from damage by
the cables. Application and removal of corner protection
adds further time and expense to the loading and unloading
20 operations.
Summary of ,~.he Inyention
The invention provides a center beam railcar that
addresses the above concerns without unduly increasing the
weight or expense of manufacturing the car. The railcar of
the inventor preferably provides increased volume capacity
and can be loaded and unloadec by overhead crane. The car
a3.so preferably provides 3r'. improved system for securing
loads_
Preferably, the center beam car of the invention hay
sufficient volume ca~~acity to enable the full weight
capacity of the car t_o be utilized with certain loads.
Thus, the car can "gross out" and "cube out" at the same
time with, e.g., kilra-dried lumber products.
Tn contrast with. the top chords that have been used in
center beam railcars in the past, wherein the top chord is
significantly wider than the intermediate portion of the
canter beam below the top chord, the preferred center beam
railcar has a narrow top chord that does not interfiere with
loading by overhead crane, but still contributes
significantly to the strength and load carrying capacity of
the railcar. The top chord is preferably of a generally
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rectangular, tubular configuration, and has a width
substantially equal to or slightly less than the width of
the intermediate portion of the center beam therebelow.
This permits the load to be stacked alongside the top chord,
increasing the volume of lading that can be accommodated as
compared with earlier center beam cars in which the lading
generally could be stacked only as high as the bottom of the
top chord. The top chord preferably is at a height slightly
above the upper ends of the bulkheads.
1.0 To further increase the volume of lading that can be
carried, the railcar preferably has a depressed central
portior~. In combination with the zlarrow top chord, this
preferably provides a cleax loading height of at least about
14 feet above the dsapressed central portion. The depressed
central portion is located between a pair of higher end
portions each preferably having a length about equal. to the
length of products to be carried thereon, or a multiple
thereof. Tn one particular embodiment, the length is about
16 feet. The depth of the depression is similarly selected
to accommodate products to be carried thereon in a manner
that facilitates flexibility in loading products of various
sizes. Trl one embad:imea: the depth is 16 ir~. , to enabl=
the depressio~a tc accommodatE bundles of engineered wood
products hav~.ng a heighC of 15 ~ in " with the tops of the
bundles being at about the same level as the adjacent end
portions of the deck.
To increase ver9atility in securing the lading on the
railcar, the lading is preferably secured by straps, each
having a first end secured on a first side of the railcar,
and a second end secured on the opposite side of the
railearj with the strap extending over the top chord for
materials that are stacked up to the top chord, and with the
strap extending under the top chord for materials which are
not stacked as high.
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In the preferred embodiment of the invention, the straps are
secured at or near t~ze side sills on both sides of the car, thus
avoiding the need for workers to climb onto the deck or onto the load
to secure the load. This also eliminates the need to provide winches
on both sides of the c:ar. Winches may be provided only on one side,
with a simple mechanism for securing a strap end provided on the other
side. Furthermore, to increase versatility, the winches and mechanisms
that are used to retain the ends of the straps preferably are
longitudinally adjustable in tracks on the side of the railcar.
The straps may be passed over the lading from one side of the car
to the other by coiling a portion of the strap containing a free end,
while leaving the other end attached to a winch, and manually tossing
the coiled strap portion from one side of the car to the other. This
may be efficiently accomplished by a worker standing with his or her
back to the railcar, tossing the coiled strap over his or her shoulder.
At its ends, the center may include one or more elongated
supports that connect t:he bulkheads to one or more posts . The supports
need not be connected to the center sill or to the top chord.
In summary of the foregoing, therefore, the present invention may
be considered as providing a center beam railcar comprising a deck
including a depressed central portion, bulkheads at opposite ends of
the railcar, and a center beam extending longitudinally of the railcar
and including a center ,sill, a top chord, and an intermediate structure
connecting the top chord and the center sill, wherein the top chord has
a width that is not substantially greater than the width of said
intermediate structure.
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Brief Description of the Drawinc(s
Fig. 1 is a side e:Levational view of a railcar in accordance with
a first embodiment of t:he invention. A horizontal member connecting
the bulkhead to the nearest vertical post at a position about half way
up the bulkhead, shown.at the right hand end of the car in Fig. 1, but
not at the left hand end of the car, may be included at both ends of
the car.
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Fig. 2 is a schematic sectional end elevational view of
the car of Fig. 1, shown on an enlarged scale, showing in
cross-section the center laeam, a bolster, and a cross bearer
in a depressed deck portion.
Fig. 3 is a schematic plan view of the railcar of Fig.
1 with portions omitted for clarity, showing the center sill
and cross bearers on the left half, and showing the top
chord and floor sheets on the right half.
Fig. ~ is a schematic end elevational view of the
railcar of Fig. 1.
Fig. 5 is a side elevational view of a railcar in
accordance with a second embodiment of the invention_ Two
alternative end structures axe shown- At the left end,
there is shown a single horizontal structural member
connecting the bulkhead with the closest two vertical posts.
At the right end, there are shown two horizontal structural
members connect~.ng the bulkhead with the closest two
vercic.ai posts. Either of these structures may be used at
both ends of the railcar in the second embodiment of the
2U i~7vent~.ori.
Fig. 6 is a schematic sectional end elevational view
thereof, shown on an enlarged scale, illustrating in cross-
sect~ion the center beam, a bolster, and a cross bearer in a
depressed deck section.
fig. 7 is a plan view of the railcar of Fig. 5, with
portions omitted for clarity.
Fig. 8 is a schematic end elevational view of the
railcar of Fig. 5.
Fig. 9 is a partial side elevational view illustrating
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a third embodiment of the invention which is similar to the
embodiments of Figs. 5-8, except for the configuration of
the ends of the center beam.
Fig. 10 ie a scY~ematic end elevational view of the
railcar of Fig. 9.
Fig. 11 is a schematic sectional view thereof, Gaken at
the depressed deck.
Fig. 12 is a schematic sectional view thereof, with a
cross bearer at the upper deck shown in solid lines, and a
section at the bolster shown in broken lines,
Fig. 13 is an oblique view of the embodiment of Figs.
9-12.
Detailed De~cx~.gtlon of preferred Embod~.ments
The invention is preferably embodied in a center beam
car for transportation of lumber products or other bulky
loads comprising a deck 10 for supporting the load, a censer.
beam ~2 extending longitudinally of the railcar, and a pair
of bulkhead4 14, one zit each end of the car, to constrain
the lading against lox~gitudinal displacement. The car is
supported by a pair oi_ trucks 16 and bolsters 18 near its
opposite ends. The deck is supported by a center sill 20, a
pair of side sills 22, and a plurality of cross-bearers
and/or cross-ties 24. The deck may comprise floor sheets 26,
which are preferably i.x~clfned inward toward the center beam,
but whic2~. may be horizontal. To facilitate loading and
unloading of certain loads, in some embodiments risers 24a
(Fig. 13) may project. above the top surface of the floor
sheets, Stringers may be attached to the bottom of the
floor sheets to stiffen them. The sides 28 of tkie center
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beam above the deck preferably are substantially
perpendicular to the deck sur'_aces that support the lading,
and accordingly are preferably either vertical or inclined
sl,ightl.y inward, depending upon the orientation of the load-
s supporting surface. straps 52 or cables and winches 30 are
preferably provided to secure the lading. The floor sheets
26 may be welded to r_he center sill 20, side sills 22 and
cross bearers 24, or may be welded to the center beam and
cross bearers only. Tn the latter case, the outer edges of
the floor sheets may be bent down between the cross bearers
to provide additional. stiffness, or the outer edges may be
supported by stringers..
The center beam 12 preferably acts as a principal load-
bearing structural support for the car to support the weigh
of the car and the lading. The center beam includes a top
chord 32 that bears substantial compression loads. The top
chord 32 is connected with the center sill by an
intermediate structure thar_ preferably comprises a plurality
of vertical posts 34 and a piuraiity of diagonal braces 36.
The vertical posts may be of Z-shaped cross-sect~.on, as
shown in Fig_ 3, or may be I-beams, as shown in Fig. ~, or
may be of other conf igurati~ons . The diagonal members 3 ~ m.;~
be tubular, or may be of other co:afigurations. The heighr
of the center beam is preferably greater than or equal to
that o~ the bulkheads..
To facilitate loading and unloading of the railcar
using overhead cranes, and to facilitate loading of the car
to a height above the bottom of the top chord 32, the top
chord preferably is configured so as not to project beyond
the sides of the intermediate structure immediately
therebeneath 3$. Thin, the top chord in the preferred .
embodiment hag a width that is about equal to or slightly
Less than the width. o.f the adjacent intermediate structure_
zn the illustrated embodiment, the sides of the top chord
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are positioned slightly inward of the sides of the
intermediate struct:ure.. This configuration may be
contrasted with the configuration of center beam care in the
prior art wherein t:he top chords have projected outward from
the surfaces therebelow. See, e.g., U.S. Patent No.
3,244,120 and No. 3,'734,031.
Notwithstanding its reduced width, the top chord 32
herein is one of the prir~cipal longitudinal load-bearing
members of the car, and the superstructure of the center
beam, i.e., the top chord 32, vert~.Cal posts 34 and diagonal
braces 36, Contribute substantially to the strength of the
center beam, and thus to the weight-carrying capacity of the
car. Ta provide the top chord with sufficient strength.
stiffness and durab.lity for lozxg term usage in commercial
rail transport, the top chord is preferably a tubular
structure of gen.eral.ly square or other rectangular cross
secCion.
To increase the volume of :Lading that can be
accommodated by the railcar while maintaining versatility in
2C~ accommodating ladings of various shapes and sizes, the de~k
preferably has a depressed center section or well aG oz
sufficient length Co~accommoctatE large bundles of products.'
while leaving uninterrupted end portions 42 of substantial
length that can also support large bundles of products. Ir_
one particular embodiment'., she length between bulkheads 14
is 73 ft., and the length of the depressed center section 40
is 40 ft., leaving end sections 42 of about 16 ft. in length
each. The 16 ft, end sections 42 may be used, e.g. for
loading studs or other products having lengths of 8 ft. or
16 ft.
The width of the loading surface on each side of c~le
center beam is about 4 ft_
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'The center section may be depressed by any desired
dimension, subject to clearance limitations and other
practical constraints. 1n some embodiments, the center
section 40 is depressed s6 in. to accommodate bundles of
engineered wood products having a height of 15 ~ in. zn
other embodiments, a 19 in, depression maybe employed. zn
still other embodiments, the depth of the depression is 30
in. Where products of varying densities are to be shipped,
to facilitate maintaining a sufficiently low center bt
'gravity for the car when fully loaded, products of higher
density Such as ~VL may be loaded in the depression, with
products of relatively lower density such as engineered wood
products being loaded thereabove,
The depressed center section ~k0 and narrow top chord 32
combine to increase the clear loading height_ Preferably,
the clear loading height ~.s aver 14 ft. These features not
only make increased volume available for lading, but also
enable the car to transport irregularly-shaped products that
might be difficult or impossible to transport efficiently or
earlier center beam ears.
In the preferred embodiment, the underframe and the
posts 34 assist substantially in supporting the top chord 32
against buckling in the horizontal plane. Under static
loading conditions when the car is fully loaded, the top
chord 32 and diagonal braces 36 sire loaded in compression,
and the center sill 20 and posts 34 are loaded in tension.
To reduce compression loads on the narrow top chord, the
strength and stiffness of the posts may be increased by
increasing the widths of their flanges 42, and the strength
and stiffness of the diagonal braces 36 may similarly be
increased. Also, the center sill 20 in the preferred
embodiment has a fish belly configuration, wherein the
center sill is relatively sklallow adjacent the bolsters, but
inward of the bolsters the bottom of the center sill slopes
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downward to provide the center sill with a deep central
portion 42.
The unloaded car preferably has a weight not greater
than about 70,000 lbe. In some embodiments, the weight of
the car is about 64,000-66,000 lbs.
Preferably, tree railcar is capable of carrying at least
about 110 tons of wood products having a density of about 3C
lbs. per Cubic foot without exceeding the AAR Plate F
clearances. The AAR Plate F clearance template ig shown «t
l0 60.
The preferred mechanism for retaining lading on the
railcar employs straps 52, rather than cables, and izwolves
securement of the straps at low elevations on opposite Sides
of the railcar, with one end of each strap secured on one
side at or near the side sill, and the other end of the
strap secured on the other side of the railcar, at or near
the side sill. As showy i: i~ia. 2, the strap 52 is passed
over the Zading 54 and, where the lading is stacked to the
top chord 32, is passed over the cop chord. Where the
lading is not stacked to the height of the top choxd, as in
Fig_ 6, the strap may be passed under the top~chord to the
other side of the railcar. The straps are preferably of a
nonstandard width, e.g., 4 ~ in., to reduce the possibility
of the straps beizlg misappropriated for use in other
applications.
Rather than including winches on both sides of the
railcar as in the past., winches 30 are preferably provided
on only one side, with one or more connecting mechanisms 56
provided on the other side to secure the free ends of the
straps 52. The winches 30 and connedting mechanisms 56 are
preferably longitudinally adjustable along tracks 58 (Fig.
5) so that the longitudinal positions of the straps may be
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adjusted to increase versatility in handling load components
of various dimensions. To avoid requiring workers to be
positioned on the railcaY to secure and release the straps,
the tree end of then strap 52 may be thrown manually from one
side of the car to the other. This may be accomplished by a
worker standing facing away from the railcar, tossing the
rolled up strap over his or her shoulder to the other side
of the railcar. To facilitate this, a weight may be
attached to the free end of the strap, or to a tether
attached to the free end of the strap.
As an alt2rnat.i,ve, or in add~.tion to the use of straps
rather than cables, to protect corners of wood product
loads, corner protectors may be included as integral parts
of the wood product bundles.
l5 Tn the embodiment o~ Figs. 1-4, a diagonal brace 36
connects the top of t:he bulkhead 14 to the center sill 20.
A~ shown at the right:-?lan.d end of the center beam in Fig. 1,
an additional horizor_tal. brace 45 may connect the bulkhead
to the d~.agonal brace a:~d/or to the nearest post 34. The
2o horizontal brace 46 is positioned apprax,imately halfway up
the bulkhead.
Tn the embodi.menr_ o~ Figs. 5-8, at the ends of the
center beam 12, one oz- more structural members may connect
the bulkhead with one or more posts 34, without being
25 connected to the center sill 2Q or to the top chord 32, and
wi;.hout any of the diagonal members 36 being attached to the
bulkhead. Tn the arrangement shown at the left in Fig. 5, a
single horizontal member 48 is connected to the bulkhead 14
and to each of the two po9tq 38 closest to that bulkhead,
30 about midway between the top chord and the center sill,
without being connecting to the center sill or to the top
chord. Irr another arrangement, shown at the right in Fig_
S, two horizontal structural supports 50 are connected to
..
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each bulkhead 14, and to the two pasts 34 closest to that
bulkhead, without being connected to the center sill or to
the top chord. The two horizontal supports may be spaced at
about 1/3 and 2/3 of the height of the cEnter beam.
From the foregoing, it should be appreciated that the
invention provides a novel and improved center beam car.
The invention is not limited to the embodiments described
above azid shown in the accompanying drawings, nor to any
particular embodiments. The invention is particularly
pointed out and further described in the following claims.
